Mitsubishi ML520G71...Red Holy Grail or Flashlight Fail ??

CDBEAM,
I don't see how the math works out. In order to get something like 1 mrad divergence from a collimated diode that produces over 8mrad with it's near field beam width of 0.5mm will require this dimension to be expanded to aprox. 4mm and when knife edged this will mean a 3 diode stack will have a 12mm width. You can stack 8 LOC 826 diodes in this same beam dimension of 4x12mm and reasonably produce 2.0W of 655 nm light. The LOCs will be two to three times dimmer, but the diode cost will be 1/3 as great and the additional diode mounts,flexmounts, and mirrors will balance the costs of the lenses required by the Mitsubishi diodes. The LOCs produce a richer red. On the other hand there are more "things" to align. The Mitsubishi diodes will be brighter but it will cost a lot more when you blow a diode (you don't blow mounts or mirrors), so how gutsy willy you be about over-driving? The alternative these diodes present are +/-, maybe good for some applications,but not an overwhelming choice.

its going to be three times dimmer and the diodes are stupid sensitive?

sorry but to me LOC's are WORTHLESS

I have tired many, many times to make a laser with LOC's and failed... you just look at the fuckers the wrong way and they LED on you... complete trash

never had a problem with 445's though

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Originally Posted by flecom

3w 4.5mm x 4.5mm 637 would be awesome... where do I sign up?

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Butbutbut... we're never going to have enough green to match!

Unless we can convince a certain Allen to pull apart his Laserscope. ;)

Mr.Planters ... My ML520G71 test set up is being updated with a P3 driver and a proper holder for Drlava's C-Lenses. When it was operating...I measured the beam after the C lenses...and got 4mm x 1.5 mm. At 13' (4M), the beam profile was 8.25mm x 7mm. Using Pseudonomen137's mRad Calculator...I plug in 0 feet,4mm, 13 feet and 8.25mm...and 1.07 mRad is what is said. Perhaps I am not using this application correctly ??? That is possible ??

4mm + 4mm + 4mm does equal 12mm...but would that not be _ _ _ when I want to stack l l l or 1.5 + 1.5 + 1.5 ??? I am confused !! Yikes !!

Anyway...I assume these beams can be knife edged.....BUT...I did forget...that there must be some seperation between the beams....about .5mm should provide full output for each beam. You have more experience with knife edging...than a sushi chief haha !! Is this correct ?? So....this is what I have observed on my dual 445 set up...and I assume it would apply for the ML520G71 or the new ML501P73...not sure.

Point is that if one tried to knife edge three beams...I suppose the result would be 5.5mm x 4mm...( 1.5 + .5 + 1.5 +.5 + 1.5 ) ?? Perhaps...only a quad would be practical ??? That might end up with an aperature beam profile of 3.5mm ( 1.5 + .5 + 1.5) by 4mm. That would be my thought...for now. I think performance is still being determined....and while I am encouraged...I am realistic. Thanx.

CDBEAM

Regarding Stoney's post...More Red, More Green, More Blue....Yikes...More Green, More Blue, More Red....It NEVER ENDS !!!

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Flecom:\Quote:its going to be three times dimmer and the diodes are stupid sensitive?

sorry but to me LOC's are WORTHLESS

I have tired many, many times to make a laser with LOC's and failed... you just look at the fuckers the wrong way and they LED on you... complete trash

never had a problem with 445's though

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635 vs 660 argument again? It's preference. Some call 635 "orange" some call 660 "dim" The 660 (658-whatever) I can barely see, but very nice tight beam. 638s are troublesome and fatt even after taming. Large galvo mirrors. That's the plan 4me . I got new (old G-120s) in (thanx Bart), and 12x12 is the mirrors I'm gonna cut for them Attachment 27930

or you can get the semrock dichro and do both 635 and 660 :p

thats what I do... the deeper red does not do much for beam shows tho... even significantly lower power 635/642 is a lot brighter than 660 at reasonable power... and as far as the "tint" of red, if you can't see it who cares if its "proper" or not? *retardo

CDBEAM,
If your getting 8.25mmx7mm at 4,000mm then you are getting approx. 2mrad full angle divergence This is the standard used to compare these sources ( I suspect the calculator is outputting 1/2 angle divergence). Based on your initial beam size of 4mmx1.5mm you would need 8mmx3mm to get down to 1 mrad. This is pretty close to solar fire's results. If you knife edged 3 then you could get 8mmx9mm if you were very tight. That would be 12 LOCs if they were very tight. I would measure your divergence at a longer baseline in any case, this should make it easier to get a more accurate comparison. 1mm vs.1.5mm vs.2mm is a small measurement especially with glare and surface absorption, but it is a very large relative difference. Use a folding mirror at 4,000mm and bring your far field right back next to the source. This way as you focus the collimator you can look directly at the spot.
Flecom,
I have 16 LOCs putting out 4.5W at 645nm (cooled) in a .8mrad beam. The color is very rich and the graphics impressive, but I am not in love with the LOCs. I kind of hate them. I replace them like mints. It feels nice when I turn on the projector and they all are working. I might have missed this and I am not being facetious, but are these 520G71s more robust? I mean not just in terms of an additional 100-200mw, but like the 445s, to mysterious death? Do we have some track record that they just last. Like dnr, I did some multi-day longevity tests on the LOCs and when treated with strict isolation in the corner of a room they ran for nearly 100 hours at 400ma. before they went LED. But, in real world projectors they blow more frequently than these tests implied and at more conservative power levels as well. So if these new diodes are really tough then I give, I'm sold.

Hey beam,

I was just playing with the divergence calculator and the numbers you stated. If you are using the 4mm @ 0 feet/meters then you are measuring the wrong axis. Using 4mm and 8.25mm you get 1.07mrad as you claim, but as stated, it’s the wrong axis. You need to use the horizontal measurements of the beam @ the cylinder lens and the far field. It’s the divergence of the corrected axis which you want to determine. Beyond that you need to increase your distance to get more accurate measurements, at least 10m.

How in the world did you measure 8.25mm, I can’t even measure that with a measuring grid?

PS
The best I see coming out of these diodes is a dual (PBS) with an a beam size @ the aperture of 4mm x 4mm and 1.07mrad divergence (with 8x cylinders) or a quad (knife edge + PBS) with a beam size @ the aperture of 4mm x 4mm and 1.42mrad divergence (with 6x cylinders) or a Hex with an a beam size @ the aperture of 5.5mm x 5.5mm and 2.5mrad divergence (with the lava cylinders).

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Originally Posted by planters

are these 520G71s more robust? I mean not just in terms of an additional 100-200mw, but like the 445s, to mysterious death?

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if the torture tests over at LPF are any indication they are similar to the 445's in terms of taking abuse

your setup while very impressive is unrealistic for most people (myself included) and their unreliability/sensitivity makes them completely useless to me

also anyone notice o-like seems to allegedly have the 500mW version of these?

http://www.o-like.com/index.php?main...kslcpfs8pn1ag2